Attachment for fluid pumps



April 20, 1954 G- BAXANDALL ATTACHMENT FOR FLUID PUMPS Filed April v6, 1951 I N V EN TOR. fimrma/l,

Patented Apr. 20, 1954 ATTACHBIENT FOR FLUID PUMPS Gerald Baxandall, Kensington, Johannesburg,

Union of South Africa, assignor to The Wayne tion of Maryland Pump Company, Fort Wayne, Ind., a corpora- Application April 6, 1951, Serial No. 219,747

1 Claim.

This invention relates to a new and improved dispensing pump and more particularly to a pump of this type having interlocking means whereby the pump cannot be operated without resetting the dials which record the liquid dispensed.

Pumps of this type are provided with an interlock between the switch which controls the motor 101 d iving thev pumpand' the indicating counter for indicating the quantity delivered so that the motor cannot be started without resetting the indicatingcounter to zero. The interlock is put into operation by hanging up the nozzle after a dispensing operation, the butt of the nozzle engaging and moving a lever called a nozzle lever. The motor switch is closed by manual movement of the nozzle lever after removing the nozzle for the next dispensing operation. The nozzle lever cannot be given this manual movement, however, unless the counter has been returned to zero because of the'interlock.

Aninterlock of this character is important in preventing a false indication of the amount delivered whether that false indication be given intentionally or accidentally. In many jurisdictions such an interlock is required by law so as to prevent indications and consequent erroneous charges for the amount delivered.

While dispensing pumps of this character are normally provided with electric motors for driving the pump. it is desirable in many instances to provide such pumps with means for manual operation. Such manual means may be desired for use in cases of temporary failure of electric current supplyor in some instances pumps may be installed beyond the range of present electric power. distribution but where such distribution is expected to be extended.

Since the usual type of interlock above described is only effective to prevent turning. on the current tothe motor it. does not. prevent operation of the pump by hand and'consequently is ineffective in cases where a pump is provided with means for manual operation.

It is an object of the present invention to provide a dispensing pump with an interlock preventing manual operation of the pump.

It is a further object to provide an interlock which is mechanical and positive in action, preventing operation of the pump by either mechanical or electrical means.

It is an additional object to provide blocking means acting upon a drive member of the pump and positively preventing movement of said memher.

It is also an object to provide an interlock of this type which is connected to the usual type of switch control interlock so that it may be oper ated thereby;

It is another object to provide an interlock controlled blocking means which is simple in design and construction and adapted to be added to existing pump and interlock structures without material alteration thereof.

Other and further objects will appear as the description proceeds. Y

I have shown certain preferred embodiments of my invention in the accompanying drawings in which- Figure 1 is an elevation of a dispensing pump with my interlock appliedthereto, the housing being partly broken away to show the mechanism;

Figure 2 is a fragmentary view, on an enlarged scale, showing the interlock mechanism and Figure 3 is a fragmentar side elevation showing the handle for manual operation.

In the drawings, the dispensing pump is shown as enclosed in a housing I l which is largely broken away in Figure l to show the interior construction. The pump, as shown, comprises an electric motor is having a drive sprocket Hi connected by drive chain I6 toa drive sprocket 18' on the pump 20. The fluid deliveredby the pump passes through pipe 2| and other piping to the hose 23. The complete connections are not shown as the specific structure of this portion of the apparatus is well known and forms no part of the present invention.

The counter mechanism 24' is driven by the fluid delivered in the well known manner and indicates the quantity which has been delivered. This counter and indicating mechanism has a. reset shaft 25 actuated by handle 27. This shaft 25 extends through the counter mechanism 24 and is interconnected to interlock 2.8on the right. side of Figu-rel. Thenozzle-hook. is provided to re ceive the nozzle at 32 when the pump is not in use. The nozzle lever 34 is moved inwardly in the clockwise direction about its pivot 35 when the nozzle 32 is put in position on the hook 30. This lever 34 is connected by link 31 to the bell crank lever 38 which connects with the interlock 28 and has its movement controlled thereby. The motor switch rod 40 extends downwardly from the lower arm of the bell crank lever 38 to operate the motor switch 42. This mechanism forms no part of the present invention and is also well known in the art.

The transverse shaft 44 carries the sprocket 45 which serves to drive the chain 41, this chain passing around the small sprocket 48 on shaft 49. Also secured to shaft 49 is a larger sprocket 5| which has a driving connection with the small sprocket 53 on the pump 20 by means of chain 55.

The arm 51, shown on an enlarged scale in Figure 2, is pivoted on the shaft 44 and has a side arm 59 to the end of which is pivotally connected the rod 6|. end of rod BI is connected by means of collar 62 to the lower portion of the motor switch rod 40. The blocking member 64 is pivotally supported at 65 on the lower end of the arm 51. The outer face of the blocking member 64 is provided with a plurality of arcuate recesses 61 adapted to interfit with the drive chain 41, as clearly shown in Figure 2. A pair of spaced guide members 69 extend from the lower side of blocking member 64 on each side of chain 41 so as to maintain the blocking member aligned with the chain. The stop pin 10 is carried by the arm 51 adjacent the stop surface 12 on blocking member 64. This surface 12 cooperates with stop pin 16 to permit a limited swinging movement of the blocking member 64 about its pivot 65. Consequently, the

arcuate recesses 61 will be able to fit about the I chain members when the arm 57 is swung to the left to bring the blocking member into engagement with the chain.

The stop 10, however, limits the counter-clockwise movement of the blocking member 64 so that once the blocking member is fully engaged with the chain 41 it will prevent downward movement of this run of the chain. It will be understood that when manually operating the pump the pulley 45 is turned in the counter-clockwise direction, as seen in Figure 1, which movement causes the run of chain 47 which can be engaged by the blocking member 64 to move downwardly. As shown in Figure 3, a handle 75 is provided for-engagement with shaft 44 so that the pump may be operated manually.

In the operation of the pump, when the nozzle 32 is removed from the hook 30, preliminary to delivery of fluid by the pump, the nozzle lever 34 is manually pulled outwardly or swung in the counter-clockwise direction about its pivot 35. This movement pulls on the link 31, rotating the bell crank lever 38 in the clockwise direction about its pivot and lifting the motor switch rod 40. This movement of rod 40 serves to close the motor switch and if electric current is supplied to the pump the motor will operate.

This upward movement of rod 40 will also push the rod 6| upwardly and that rod 6|, through the side arm 59, will swing the arm 51 in the counter-clockwise direction about the shaft 44. This withdraws the blocking member 64 from contact with the drive chain 41 so that that chain is free to move. It will be understood that the actual delivery of fluid is controlled by the usual nozzle control lever 11 on the nozzle 32.

4 If no current is available for operation of the motor l3, the parts will be freed so that by manual rotation of the handle fluid may be de- As shown in Fig. 1', the lower livered. It will be noted that the chains and sprockets connecting the shaft 44 and the pump multiply the rotation of shaft 44 so that the pump shaft is rotated more rapidly than the manual drive shaft 44 with the parts connected as shown. The manual rotation of the pump will simultaneously rotate the motor rotor through drive chains 16, unless a suitable clutching device is provided to disengage it.

It will be understood that the usual type of interlock 28 will prevent movement of the nozzle lever 34 unless the counter has returned to zero position through rotation of shaft 25 by manual operation of the handle 21. The blocking member 64 is returned to blocking position, as shown in Figure 2, whenever the nozzle 32 is replaced on its hook 30. Consequently, it is impossible to rotate the shaft 44 manually unless the nozzle lever 34 is manually swung outwardly since the movement of the drive chain 41 is positively blocked.

By means of the constructions shown, it is possible to operate the pump either electrically or manually until the counter has been returned to zero and the interlock 28 releases the bell crank 38 so that the nozzle lever 34 maybe pulled out manually to operate the switch and to unblock the drive chain 41.

While I have shown certain preferred embodi ments of my invention, it is capable of variation to meet differing conditions and requirements and to adapt it to different forms of pump constructions. I therefore contemplate such modifications as come within the scope of the appended claim.

In the claim:

In combination with a dispensing pump, means including a chain drive for operating the pump, blocking means movable into and out of engagee ment with the chain, said means when in engage-1 ment with the chain preventing operation of the pump, a. lever for moving said blocking means, a counter for indicating the quantity of liquid dispensed by the pump, and an interconnection between the counter and the lever for moving the blocking means whereby the blocking means is prevented from movement out of engagement with the chain when the counter is in other than the zero position.

References Cited in the file of this patentr-Q;

UNITED STATES PATENTS Sturm et al Dec. 5, 1939 

